Cyclic control program system



Feb. 9, 1954 2,668,589

CYCLIC CONTROL PROGRAM SYSTEM Original Filed May 7, 1949 2 Sheets-Sheet1 FIG. 12 Q \jnullll 5 INVENTOR.

Douglas E Illiun ATTYS Patented Feb. 9, 1954 UNITED sATENr FOFEFEICECYoflIoooNTRoL PROGRAM SYSTEM Douglas-F. Illian,';0ak'Park,Ill'.,'assignor toGhgera l Electric Company, a corporation' of 'New'"York 6 Claims. "1 The presentinvention"re1ates to 'cyclicfco'ntrolprogram systems and 'i'nore. particularly to se lecting switches forsuch systems. This-application is a division bf the oope'nding-application Of Dbliglas 11118111, SEIl'aI NO; 9130i), filed May 7;-l949f1lbwPfil'ifNO. 2,624,352

111 the lllian ap lication mentioned there 'iS dis'lbs'edah eltiic6611172661 SyStm fol dishwashing apparatus of the character of thatdisclosed l'h the (iopendifigafipliatioh bf'Edg ar s. Stoddard;SilQT'NO. S QZQLF fiId A pi il 8 1949. This (idntldl'SyStlfig6l/rfitheoperation'of the apparatus 130 pert 615m "automatically and in 115F6-determined sqliilillh sfili's ifillidifig' ingfWash ing, 'rinsi'ngffan'ddrying 'o'f the dishes and other --iitehsils' eontaineu the apparatus;A180 this a paratus dmfifiS es a fiabifie t housing a verticallydisposed vat'mcmdmg a'front'opn ing and adoonforclo'sing'the'irontopening, the door being mounted 'for movement'sbetween a substantiallyvertical closed posit-ion and-a-sub' stantiallyhorizontal open position. Further this apparatus c'omprises rackstructure Y for suppoit ing the dishes and other'utensils that'is'inovable over the doorin'its open position 'intoantl out of the vatthrough theiront' opening 7 It-is the general objeot'of the presentinvention to provide a program =sl'ectingsystenilthat may be readilyincorporate'ddnto adishwashei',

clothes Washer, or other -apparatus, for the purpose of controlling'thecycle of operation; thereof. Another object of the invention'is toprovide an improved cyclic control system incorporating an lectro-res'pons'ivetime-governed circuit oon-- troller. i I

'A-further object of theinvehtioh is to provide an improved" programselectingswitoh of the combined inanual and timer controlled type.Further featuresof the invention; pertain to the particulararrangementof the elements of the cyclidcontrol program system asset thecircuitto'ntroller incorpdfatedthrem, whereby theabove=outlined"and'atiditiohal"dperating fea tures' thereof "are'attaihed."' 'The invention; 'bo'th as to Reorganization method ofoperation, together ith {further ob"- jects andadvantages*tuereoawnrbest'be' underdrawings-fi m which Figure "l l is "afroht elem-- tio'nal'vi'ew; partlybroken away, of dishwashing apparatusincorporating a, cyclic control program system ehibo'dyingthe presentinvention Fig; 2' is a vertical "sectional view'of the dishwash'ingapparatus} taken in the "direction of the arrows along theline L-Z 'ihFig.1; Fig. Bis an enlarged fragmentary' sectional view" of" the circuit(5on Holler-incorporated in the control"circuit of the dishwashing-'apparatusshown' in Figs. 1 and 2, certain of'the elements of thecircuit controller being diagrammatically illustrated; and Fig. 4; is anelectric diagram of'the circuit controller and the circuit controlarrahgement incorporated in the'dishwash'ingapparatus shown in Figs. 1and 2.-

Referring now to Figsxl and-'2 of the drawings, there is generallyillustrated "dish-washing apparatus lll' of the character of thatdisclosed. in the previously mentioned "Stoddard applica tion andincorporating a *cycliccontrol circuit embodying-the" features of" thepresent invention. The'dishwashing apparatus in is of thegasketles's-door front-openingtype including a cabinet I l housing asubstantially vertically disposed vat l2, thecabinetfll and the vat 12having substantially aligned front openings that are closed by afront'door F3. The front door'lSis pivotally mounted 'adjacent tothe-lower edge thereof Withinthe lowerportion of the vat 12 and ismovable between a substantially vertical closed position andasubstmtially horizontal open position; "Alsothe dishwashi'ngapparatusl0 com prises-'movab'lera'ck structure, not shown-that isadaptedto=support dishes-and other utensils Withinthe vat'l'l."forwashing p-urposes, the rack structurebeing movable into and outof the vat l2 through the front openings when 'theooor' ['3 occupie'sit's open position. impeller 14 is arranged within a "sump' l t formedin -"the lower portion of the vat l2 and is rotated by an associatedeledt'ric operating motor fit 1" or the purpose of producing aWashingaction Within the vat 1'2 when "the doorl occupies itselos'edposition and Washing --liquid is contained in 1 the sump i5. I

For the purpose of supplying 'washingliquid to the vat 12 there ""is'provided an inlet hondiiit l1 cofinected {to a"s'ui'tablesource "ofWashing The ihletconduitdl communicateswith the inlet port of an inletvalve I8 of the solenoid controlled type; and the outlet port of theinlet valve I8 communicates with a conduit I9 that is connected to aspraying device 26 arranged in a depression 2| formed substantiallycentrally within the top Wall of the vat I2. The inlet valve I8 is ofthe fast-opening, slow-closing type, being governed by an associateddashpot so as to prevent water hammer in the plumbing cornmunicatingwith the inlet conduit H. The inlet valve I8 is normally biased to itsclosed position, and when the solenoid I8 thereof is energized it isoperated into its open position in order that washing liquid may besupplied from the inlet conduit I! to the spraying device 26, wherebythe washing liquid is sprayed downwardly from the top of the vat I2through the rack structure, not shown, and accumulates in the sump I5.Subsequently, when the solenoid I3 of the inlet valve I8 is de-energizedit moves slowly from its open position to its closed position in orderto cut off the supply of washing liquid from the inlet conduit I! to thespraying device 26.

For the purpose of controlling the retention of washing liquid in thesump I5, there is provided a drain mechanism or valve 22 of the solenoidcontrolled type. The drain valve 22 comprises a flexible conduit 23, oneend of which communicates with a drain fixture 24 provided in the lowerportion of the sump I5, and the other end of which communicates with adrain conduit 25 that is connected via a trap, or the like, not shown,to drain plumbing, not shown. The flexible conduit 23 is normally biasedinto its lower position in order to place the interior of the sump Iinto draining communication with the drain conduit 25 so that anywashing liquid accumulating in the sump I5 runs through the flexibleconduit 23 into the drain conduit 25; and when the solenoid 22' thereofis energized the flexible conduit 23 is elevated into its upper positionin order to cut off the draining communication between the interior ofthe sump I5 and the drain conduit 25 so that washing liquid may beretained in the sump I5. Subsequently, when the solenoid 22 isde-energized the drain valve 22 is returned to its draining position inorder to effect draining of the washing liquid from the sump I5.

I For the purpose of effecting drying of the dishes and other utensilssupported by the rack structure, not shown, within the vat I2, there isprovided a heating unit or element 26 that is preferably of the sheathedresistance conductor type. The heating element 26 is disposed in thelower portion of the vat I2 and in surrounding relation with respect tothe impeller I4 so that air blown by the blades of the rotating impellerI4 contacts the heatin element 26 and then moves upwardly into the vatI2 through the dishes and other utensils supported by the rackstructure, not shown.

The lower portion of the door I3 carries a detergent cup 29 openingtoward the interior of the vat I2 and adapted to receive a charge ofdetergent. Preferably, the detergent that is employed is of the typesold under the trade name Calgonite that comprises about 40 per centsodium hexametaphosphate and 60 per cent sodium metasilicate.

For the purpose of effecting coordinated operation of the operatingmotor I6, the inlet valve I8, the drain valve 22 and the heating element26, so that a washing cycle, including predetermined spraying, washing,rinsing and drying steps, is

4 carried out, a circuit controller 36 is incorporated in the dishwashinapparatus I6, the circuit controller 30 being arranged in the upperleft-hand front portion of the dishwashing apparatus I6 and disposedbetween the adjacent left-hand side wall of the cabinet I I and theadjacent left-hand side Wall of the vat I2. Of course, the circuitcontroller 36 is arranged exteriorly of the vat I2 and is appropriatelywired in a circuit control network, including the operating motor I6,the solenoids I8 and 22', the heating element 26, a measurin coil orrelay R46 and a door switch S4I. The measuring coil R46 is suitablysupported within the cabinet II exteriorly of the vat I2 and is of themarginal type, being provided with an armature, not shown, controllin apair of contacts 4|. As indicated in Fig. 2, the door switch S4I may becarried adjacent to the front lower portion of the upstanding ledgedisposed adjacent to the front opening provided into the vat I2 and inoperative relation with respect to the door I3. More particularly, whenthe door I3 is respectively moved to its closed and opened positions,the door switch S4I is respectively operated to its closed and openedpositions. Finally, the circuit network comprises a source of currentsupply that may be of volts 60 cycle A. C.

As best shown in Figs. 1 and 3 the circuit control 36 is of thecombination manual and timer controlled type and comprises a frontsupporting plate 5| that is carried by the cabinet II rearwardly of theextreme front wall thereof. The front plate 5i is provided with a casing52 detachably secured thereto, as well as a supporting bracket 53. Afirst rotatable shaft 54 is suitably journalled within the front plate5I and in the bracket 53 and projects forwardly through a hole providedin the front wall of the cabinet II to the exterior. A manual controlknob 55 is removably secured to the extreme front end of the shaft 54and carries a pointer 56 that cooperates with a trim ring 57 securedupon the outer surface of the front wall of the cabinet II. The trimring 51 carries indicia cooperating with the pointer 56 and includingthe off index 58 and the on index 59. Also the circuit controller 36comprises a second rotatable shaft 56 and a stub shaft 6I. The stubshaft (H is suitably journalled in the front plate 5I and in the bracket53, and the second shaft 60 constitutes a sleeve journalled on the stubshaft 6|. The shafts 66 and GI are disposed above the shaft 54 and carrya friction clutch indicated at 62. The details of the friction clutch 52are not shown but the adjacent face plates thereof are urged intofrictional engagement with each other and are respectively rigidlysecured to the shafts 60 and 6| for a purpose more fully explainedhereinafter. The shafts 54 and 60 are interconnected by speed-changegearing including two meshed pinions 63 and 64 respectively rigidlysecured thereto. The pinion 63 secured to the shaft 54 has precisely Ntimes as many teeth as the pinion 64 secured to the shaft 66, where Nequals to 3. Accordingly, the gearing effects a 1:3 speed ratio betweenthe shafts 54 and 60; whereby one revolution of the shaft 54 effectsthree revolutions of the shaft 60 and one revolution of the shaft 60effects /3 revolution of the shaft 54. Further, the circuit controller36 comprises a timer motor unit 65 of the electro-responsive type thatis carried by the bracket 53. The timer motor unit 65 may be of theTelechron type including a motor proper 66 and a gear box 61 housing theaccess;

usual speed reduction 1 gearing, the speed reduction gearing housedwithinrthe gearbox v6"! interconnecting the stubshaft :61 and the motorproper 66. The gearingwithinthe gear. box 5'! is so constructed andarranged that whenthemotor proper 66 is energized :from the 115 volts 60cycle A. C. source the stub shaft 6| is.rotated at a speed of preciselythree revolutions per hour.

In view of .the foregoing description of the circuit controller an, itwill be understood that the shaft 54 maybe manually rotated by themanual control knob 55 in order to effect .rotation of the shaft 60through thegearing Sip-$4; however, thi rotation of the shaft til is notimparted to the stub shaftfil directlyconnected by the gearing in thegear box v6! to the motor proper t6, the friction clutch 62accommodating relative rotation between the shaft 69 and the stub shafti3! by slipping action. .On the other hand, when the motor proper .65 isenergized, the stub shaft 6| is rotatedat three revolutions per hourthrough the gearing in .the gear box 6'! and drives the shaft .61]through the friction clutch s2 at the speed noted. The consequentrotation of the shaft 60 at three revolutions per hour effects rotationof the shaft 54 at one revolution per hour by virtue of .the gearing 6B3interposed therebetween. Accordingly, operation of the motor proper 66is normally effective to rotate the shaft 50 at three revolutions perhour in the counterclockwise direction and to rotate the shaft 54 at onerevolution per hour in the clockwise direction as viewed in Fig. 1. Theshaft 54 comprises an 01f position and an on position respectivelycorresponding to the oil and on indicia 58 and 59 respectively carriedby the trim ring 5'1 and cooperating'with the pointer 55 provided on themanual control knob 55. In the arrangement the on index 59 is disposedslightly more than 60 degrees in the clockwise direction from the offindex 58 so-that when the manual control knob '55 is grasped and rotatedin the clockwise direction through this angle sli htly greater than 60degrees, the pointer 56 is moved from its normal position cooperatingwith the off index 58 into an advanced position cooperating with the onindex 55. As explained more fully hereinafter, the motor proper isenergized at this time, whereby the stub shaft ti and the shaft lillaredriven at the previously noted speed in the counterclockwise directioneffecting further rotation of the shaft 5 in the clockwise direction.Specifically, the shaft 54 is further rotated atthe speed of onerevolution per hour from its on control position in the clockwisedirection back into its oil control position, whereby thepointer 55carried by the manual control knob 55 again cooperates with the offindex 58 provided on the trim ring 55. Thus, it will be understood thatafter the shaft 55 is rotated fromits 01f control position into its oncontrol position in the clockwise direction by the manual control knobit is automatically rotated further in the clockwise direction back intoits off control position by the motor proper 66 in a time intervalslightly less than 50 minutes.

Of course, the shaft 54 comprises a plurality of control positionsangularly disposed between its on control position and its oif controlposition, through which the shaft 54 proceeds see quentially as it isrotated in the clockwise direction. Also the shaft 60 comprises,aplurality of angularly disposed, control positions through which itproceeds three times incident to. one

complete revolution :of the shaft .54 asa consequence of the gearing.63-64 interconnecting :the shafts r54 andifill. Two insulating camsrespectively indicated at CI and C2 are rigidlysecured to the shaft 54and respectively cooperate with-two sets of switch springsdiagrammatically illustrated at St and S2. Similarly, two insulating camrespectively indicated at C3 and C t are rigidly secured to the shaft 69and respectively cooperate with two sets of switch springsdiagrammatically illustratedat S3 and S4. The set'of switch springs SIcooperating with the cam Cl comprises three individual springs that areadapted selectively to complete Xand Y contacts in the various controlpositions of the shaft 54-as explained more fully hereinafter.Similarly, the set of switch springsS2 cooperating withthe cam C2comprises three individual. springs .thatare adapted selectively tocomplete contacts I, and 2 in the various control positions of the shaft56 as explained more fully .hereinaften; Similarly, the set of switchsprings S3 cooperating with the cam C3 comprises three individualsprings that are adapted selectively to complete contacts I and 2 in thevarious control positions of the shaft 69 as explainedmore fullyhereinafter. Finally, the set of switch springs S4 cooperating with thecam C4 comprises two individual springs that are adapted selectively tocomplete associated contacts in the various control positions of theshaft $8 as explained more fully hereinafter. In the arrangement thesets of switch springs SI and S2 are of the three-position type, whilethe sets of switch springs S3 and S45 :are of the two-position type.

The connection and arrangement of the control network for thevariouselements of the dishwashing apparatus It! will best be understoodby reference to Fig. 4, wherein there is illustrated diagrammaticallyboth the elements mentioned, as well as a time-sequence operating charttherefor indicating the coordinate controls exercised by the cams C! toC4, inclusive, upon the asso-- ciated sets of switch springs SI to S4,inclusive. In the circuit network it is assumed that the negative lineconductor ll of the source of cur-- rent supply is connected to groundpotential and that the positive line conductor 12 of the source ofcurrent supply is insulated from ground potential. The positive lineconductor 12. of the source of current supply is connected directly to"one terminal of the door, switch. S4 l and the other terminal of thedoorswitc-h SM is connected to a control conductor '13. One terminal ofthe operating motor :6 is :connected to the control conductor l3; andthe other terminal of the operating motor EB is connected commonly to acontrol conductor "if-l andto. one terminal of the measuring coil R35],the other terminal of the measuring coil Raid being connected to acontrol conductor it. One terminal of the timer motor B55 is connectedto the control conductor 73; and the other terminal-of the timer motoris connected commonly to one terminal of the heating element 2d and to acontrol conductor 55, the other terminal of the heating element iiibeing connected to a control conductor 16. A

control conductor ii is commonlyconnectedto terminals of the respectivesolenoids. l8 and 22' the other terminal of the solenoid t8. beingconnected to one of the contacts 4| of. the measuring coil B l-ii, theother terminal of: the solenoid 22" being connected to a controlconductor I8, and

the other of the contacts;

coil R40 being connectedtoe control conductor 19. In the set of switchsprings SI, the uppermost spring is connected to the control conductor14, the intermediate spring is connected to the negative lineconductor", and the lower.- most spring is connected to the controlconductor 15. In the set of switch springs S2, the uppermost spring isconnected to the control conductor I6, the intermediate spring isconnected to the control conductor 13, and the lowermost spring isconnected to the control conductor 11. In the set of switch springs S3,the uppermost spring is connected to the control conductor 19, theintermediate spring is connected to the control conductor I4, and thelowermost spring is connected to the control conductor I5. In the set ofswitch springs S4 the upper and lower springs are respectively connectedto the control conductors I4 and I8.

When the dishwashing apparatus I is at rest the manual control knob 55occupies the position illustrated in Fig. 1, whereby the pointer 56carried by the manual control knob 55 registers with the legend offcarried by the trim ring and the shaft 54 occupies its normal offposition and the shaft 60 occupies its normal position. At this time thecam CI governs the set of switch springs SI to effect opening of thecontacts X and Y; while the cam C2 governs the set of switch springs S2to effect opening of the contacts I and 2. Similarly, the cam C3 governsthe set of switch springs S3 to effect respective closing and opening ofthe contacts I and 2; while the cam C4 governs the set of switch springsS4 to effect closing of the associated contacts.

Considering now the cycle of operation of the dishwashing apparatus ID,the person loads the dishes and other utensils into the rack structure,not shown, and moves the rack structure into the vat I2, and then placesa charge of detergent into the detergent cup 29. The person then movesthe door I3 from its open position into its closed position effectingclosure of the door switch SM, and then rotates the manual control knob55 in the clockwise direction from its off position into its onposition. When the manual control knob 55 is thus rotated in theclockwise direction the shaft 54 is rotated in the clockwise directionand the shaft 60 is rotated in the counterclockwise direction. Asindicated diagrammatically in Fig. 4, all of the control cams C I to C4,inclusive, are moved toward the left with respect to the associated setsof switch springs SI to S4, respectively. During this preliminaryrotation of the shaft 54 in the clockwise direction from its offposition into its on position, the control earns 03 and C4 respectivelyoperate the sets of switch springs S3 and S4; however, without effect,since the set of switch springs S2 retains both of the contacts I and 2thereof in their open positions; this ineffective operation of the setsof switch springs S3 and S4 by the respectively associated cams C3 andC4 being brought about by virtue of the fact that the shaft 60 isrotated slightly greater than 180 degrees while the shaft 54 is rotatedslightly greater than 60 degrees. The ineffective controls of the camsC3 and C4 with respect to the sets of switch springs S3 andS4,respectively, are indicated in dotted lines on the left-hand side and onthe right-hand side of the effective control thereof indicated in solidlines, as explained more fully hereinafter. When the shaft 54 is rotatedinto its on position, slightly over 60 degrees in the clockwisedirection from its off 8 position, the cams CI and C2 respectivelyoperate the sets of switch springs SI and S2. Specifically, at thistime, in the set of switch springs SI, the lowermost spring engages thehighest portion of the cam 01 effecting closure of the contacts X and Y;and in the set of switch springs S2, the intermediate spring engages thelowest portion of the cam C2 effecting closure of the contacts I. Also,at this time, in the set of switch springs S3, the intermediate springengages the low portion of the cam C3 effecting respective closure andopening of the contacts I and 2; and in the set of switch springs S4,the upper spring engages the high portion of the cam C4 effectingopening of the associated contacts. In the set of switch springs SI,when the contacts Y are thus closed, a direct circuit, including thecontrol conductor I4, the contacts I of the set of switch springs S3,the control conductor I6 and the door switch S4I, is completed acrossthe line conductors II and I2 for initiating operation of the operatingmotor Is. Also, in the set of switch springs SI, when the contacts X arethus closed, a circuit, including the control conductors I5 and I3 andthe door switch SM, is completed across the line conductors II and 12for initiating operation of the timer motor 66. Upon operating, theoperating motor I6 rotates the impeller I4 in the counterclockwisedirection as viewed from the top of the vat I2. Upon operating, thetimer motor 56 rotates, through the gearing, the gear box 61, the stubshaft GI in the counterclockwise direction, whereby the shaft 60 isrotated in the counterclockwise direction through the friction clutch62, effecting continued rotation of the shaft 54 in the clockwisedirection from its on position by virtue of the gearing 6463. Aspreviously noted the shaft 60 is rotated at a speed of three revolutionsper hour while the shaft 54 is rotated at a speed of one revolution perhour; whereby during the next succeeding 1170 seconds the cams C3 and C4bring about effective selective operations of the respective sets ofswitch springs S3 and S4, as explained more fully below.

After an elapsed time interval of approximately seconds, in the set ofswitch springs S3, the intermediate spring engages the high portion ofthe cam C3 effecting opening of the contacts I and closing of thecontacts 2. When the contacts I in the set of switch springs S3 are thusopened, the previously traced direct circuit for energizing theoperating motor I8 is interrupted; and a normally completed shunt,including the control conductors T4 and I8, for shortcircuiting themeasuring coil R40 in interrupted; whereby the measuring coil R40 isinserted in series circuit relation with the operating motor I6. Thisseries circuit for the operating motor and the measuring coil R45extends from the control conductor I3 via the operating motor IS, themeasuring coil R40, and the contacts Y in the set of switch springs SIto the negative line conductor II. Accordingly, the measuring coil R40is now energized in series circuit relation with the operating motor I6and meters the current drawn by the operating motor I6, which current isnot excessive at this time, since the operating motor I6 has already hadan opportunity to gain full speed and there is no washing liquid in thesump I5 in the vat I2. In passing it is noted that the measuring coilR45 is of the marginal type and is not operated to open the contacts 4Iwhen light currents are drawn by the operating motor I6, as explainedmore fully hereinafter.

aecsgsse:

9; Also; in .the set ofswitch springs S3, when the contacts. 2. areclosed,' a: circuit,i including the contacts -Y in the setiof switchsprings SI, the

controlconductors I4 and I9, the contacts 4|, theicontrol conductor II,the contacts I inthe setof switch springs S2, and thecontrol'conductorl3, is completed for energizing the inlet valve solenoid l8.This circuit for energizing the'inlet valve solenoid I8 includes theclosed contacts 4| of the measuring coil- Rflihas previously noted. Whenthe inlet valve solenoid it is thus energized the inlet valve I8 is.operated to; its. open position, as" previously explained; wherebywashing liquid'issupplied from the inlet conduit I 1 to the sprayingdevice 20: The washingliquid sprays downwardly from the spraying device20 through the dishes supported by the rack structure, not shown, andaccumulates in the sump I5. This washing liquid drains from thesump Ithrough the drain valve 22 and thence into the1drain conduit'25; Some-ofthe washing liquid in'the sump- I5 may-'be-caughtandflung upvvardly andoutwardly; through the-dishes supported-by the rack structure,- notshown, by the bladesof the-impeller: I4, :althoughthis action is notconsiderableat this time since the drain valve-22 occupies its:draining-position. Accordingly; the dishes-supportedby therackstructure, notvshowmin the-vat- I2 are subjected to a firstspraystep that-is-carried out-through atime intervalof approximately 30seconds.

At theconclusion of this firstspray step the upper springfin the set -ofswitch-springs S i engages-the -1ow-- portionof thecam C4 closing theassociated contactsandcompleting a. circuit, including the-Y- contactsof the set of switch springs SI, the control conductors I4, I8 and'll,the. contacts I of the setrof switch springs S2 and. thecontrolrconductor. I3, forenergizing the drain'valve solenoid 22.. Whenthe drain valve solenoid-22 isthus energizedthe drain valve 22 isoperated to. its non-draining position; whereby the washing liquidaccumulating in the sump I5-Lis1retainedtherein.after the adjacentsection of. the flexibleficonduit 23'is first filled with the washingliquid. At this time theinletvalve I8 stilloccupies its openpositionandthe operating motor lfi' is' running. Accordingly, thewashing liquidsprayed through the rack structure, not

shown, ,iromthe spraying deviceZO accumulates inithe. sump I5sincethe'drain valve 22- occupies itsi non-draining position. Thewashing liquid accumulatingin the-sump "I5 of the vat" i2 is caught bythe blades of theimpel-ler M and is flung'jupwardly and outwardlythrough .the rack structure, not 'sh'ownj'and' the dishes supportedthereby againstth'e wallsof the vat I2 and the door I3 ahdiagain'returns to the sump I5. The" gradually'increased'; whereby the current"traversing'the "operating motor I6 andthe measuring coil R43 is'graduallyincreased; When a predetermined quantity of washingliquidaccumulatesin the sump I 5, a corresponding predetermined load-is'iinposed upon the operating motor I 6,- whereby the currenttraversing" the operating motbnlliarid the measuring-coil R49 reaches-atity of washing liquid; thermeasuringc'oil R40 effects opening of thecontacts 4 I ,since: the measuring coil R43 is of themarginal-typezaspreviously noted. When the contacts 41 are thus: opened,the circuit for energizing the'inletvalve" solenoid I3 is interrupted;wherebythe inlet? valve It-is slowly returned to'its closed positionunder the control of the associated. dashpot. Shortly thereafter, theinlet valve I8 is com pletely closed cutting off the supply of washing,liquid-from the inlet conduit. llztoithe'spraying. device 20.

S3 engages the low portion of the--cam'C3-open'- ing the contacts 2 andreclosing the contacts I.

When'the contacts'z of the set-ofswitch springs S3 are thus opened, afurther'point'inthe:cir-- cuit for energizing theinlet valve solenoidI8" is interrupted; and when the contacts I of: the: setof switchsprings S3 arethusclosed, the-path for short-circuiting the measuringcoil R401 is-v again completed, together with thedirect circuit foroperating the operatingmotor I6. Accord--- ingly, the measuring coil R40is-de-energized bringing about reclosure of the contacts 4-1 ;how ever,without effect atthistime since-the-contacts 2 of the set of-switchsprings-Stareopen. Thus the connections above-described provide-a timedarrangement for efiecting the- 'de-energiza--- tion of the inletvalvesolenoid I8 andtheconsequent return of the inlet valve"! to itsclosed position in the event this result has-not already been broughtabout by operation ofthe-measur ing coilRAIl within the45secondszperiod' mentioned.

The first-washingstep continues for atotaltime of approximately 330seconds following the operation of the drain valve22-to its non-draining position, and within this time interval and in response to theaccumulationof-a predetermined quantity of washing liquid in the-sump5-, the charge of detergent contained in the detergent cup 29 isintroduced into the Washing liquid-in order that the first washing stepmaybe eiieotiveto remove grease and otherforeignmaterials from thedishes supported by the rack structure, not shown. Thearrangementforeintrcducing the detergent is-clisclosed-in the co pendingapplication of Forrest ArWalker, Serial No. 57,448, filed October 39,1948,'and isbased upon-the accumulation of a predetermined quantity oiwashing-liquid in the sump I5; whereby the'washing liquid accumulatingin the sump I5 is flushed or washedinto the" detergent cup '29 carriedby the inner wall of thedoor' I3 causing the detergent to be washedintothe body of washing'liquid contained inthe vat. I2, Thisintroduction of the detergent into the washing-liquid is accomplishedshortly following the-operation of the drain valve '22 to itsnondraining' position so that the detergent is present in the'washingliquid during a substantial part of the time inter val of the firstwashing'step.

At the conclusionof'the first washing step the: upper spring or" the setof switch springs S4iengages the igh portion of the cam: 04 opening theassociated contacts and interrupting the circuit for energizing thedrain'va'lve solenoid 22 whereby the drain valve 22 isreturned-to its'11 draining position. At this time washing liquid and the carrieddetergent drain from the sump I into the drain conduit 25. The washingliquid contained in the sump I5 is drained in a very short interval oftime; and, approximately 45 seconds after the drain valve 22 is operatedto its draining position the intermediate spring of the set of switchsprings S3 engages the high portion of the cam 03 again opening thecontacts I and reclosing the contacts 2. When the contacts I are thusagain opened the measuring coil R40 is again inserted in series with theoperating motor I6; and when the contacts 2 are reclosed the inlet valvesolenoid I8 is again energized; all in the manner previously explained.At this time the inlet valve I8 is operated to it open positioneffecting the supply of washing liquid from the liquid supply conduit I!to the spraying device 20; whereby the dishes supported by the rackstructure, not shown, are again sprayed and the washing liquidaccumulating in the sump I5 drains through the drain valve 22 in itsdraining position and thence into the drain conduit 25. This secondspray step is carried out for a time interval of approximately seconds;whereupon the upper spring of the set of switch springs S4 engages thelower portion of the cam C4 reclosing the associated contacts andefiecting re-energization of the drain valve solenoid 22. The drainvalve 22 is again operated to its non-draining position causing thewashing liquid to be retained in the sump I5, initiating a secondWashing step.

The second washing step proceeds in the manner of the first Washing stepdescribed above; whereby the inlet valve I8 is subsequently operated toits closed position under the control of the measuring coil R40dependent upon the load upon the operating motor I6, or under thecontrol of the cam C3 and the associated set of switch springs S3; allin the manner previously explained. In any case, after a time intervalof approximately 45 seconds following operation of the drain valve 22 toits non-draining position the intermediate spring of the set of switchsprings S3 engages the low portion of the cam C3 opening the contacts 2and closing the contacts I in order positively to insure de-energizationof the inlet valve solenoid I8 and shortcircuiting of the measuring coilR40. At this time the inlet valve I8 occupies its closed position andthe drain valve 22 occupies its nondraining position; whereby the secondwashing step continues in the manner previously explained. The secondwashing step continues for a time interval of approximately 330 secondsfollowing operation of the drain valve 22 to its nondraining position;whereupon, the upper spring of the set of switch springs S4 engages thehigh portion of the cam C4 opening the associated contacts and effectingtie-energization of the drain valve solenoid 22' and the consequentoperation of the drain valve'22 into its draining position.

Th washing liquid accumulated in the sump I5 is drained into the drainconduit 25 in the manner previously explained in a very short timeinterval; and approximately 45 seconds after the drain valve 22 isoperated into its draining position the intermediate spring of the setof switch springs S3 engages the high portion of the cam C3 againopening the-contacts I and reclosing the contacts 2. Opening of thecontacts I effects reinsertion of the measuring coil R40 in series withthe operating motor I6; and reclosure of the contacts 2 effectsre-energization of the'inlet valve solenoid I8. "The inlet valve I8 isagain operated toits openposition in order to initiate a third spraystep. The washing liquid supplied from the liquid supply conduit IT tothe spraying device 20 is sprayed through the dishes supported by therack structure, not shown, and is drained from the sump I5 into thedrain conduit 25. This third spray step continues through a timeinterval of 10 seconds following operation of the inlet valve I8 to itsopen position; whereupon, the upper spring of the set of switch springsS4 reengages the low portion of the camC4 reclosing the associatedcontacts and the circuit for energizing the drain valve solenoid 22';The drain valve 22 is operated to its non-draining position in orderagain to cause washing liquid' to accumulate in the sump I5, initiatinga firstrinsing step.

The first rinsing step proceeds in a manner substantially identical tothe first washing step described above; whereby the inlet valve I8subsequently operated to its closed position under the control of themeasuring coil R40 dependent upon the load upon the operating motor I6,or under the control of the cam C3 and the asso-- ciated set of switchsprings S3; all in the man'- ner previously explained. In any case,after a time interval of approximately 45 seconds following operation ofthe drain valve 22 to its nondraining position, the intermediate springof the set of switch springs S3 engages the low portion of the controlcam C3 effecting opening of the contacts 2 and closing of the contacts Iin order positively to insure de-energization of the inlet valvesolenoid I8 and short-circuiting of the measuring coil R40. At the timethe inlet valve I8 occupies its closed position and the drain valve 22occupies its non-draining position; whereby the first rinsing stepcontinues for a time interval of approximately seconds following theoperation of the drain valve 22 to its non-draining position; whereupon,the upper spring of the set of switch springs S4 engages the highportion of the cam 04 opening the associated contacts and effectingde-energization of the drain valve solenoid 22' and the consequentreturn of the drain valve 22 to its draining position.

The washing liquid accumulated in the sump I5 is drained into the drainconduit 25 in the manner previously explained in a short time interval;and approximately 45 seconds after the drain valve 22 is operated intoits draining position, the intermediate spring of the set of switchsprings S3 engages the high portion of the cam C3 openingthe contacts Iand closing the contacts 2 in order to effect insertion of the measuringcoil R40 in series with the operating motor I6 and energization of theinlet valve solenoid I8. The inlet valve I8 is again operated to itsopen position in order to initiate a fourth spray step. The washingliquid supplied from the liquid supply pipe I! to the spraying device 20is sprayed through the dishes supported by the rack structure, notshown, and is drained from the sump I5 to the drain conduit 25. Thisfourth spray continues through a time interval of approximately 10seconds following operation of the inlet valve I8 to its open position;whereupon the upper spring of the set of switch springs S4 engages thelow portion of the cam C4 closing the associated contacts and effectingenergization of the drain valve solenoid 22'. The drain valve 22 isoperated to its non-draining positiomin :orderzragaimto:cause-washingliquid to:accumulateimthe,sump 1'5; initiating "812 580.- 4 ndrinsing'step:

'The second" rinsing step: proceeds ina manner identical to: thefirst'rin'sing step described above; WhBIBbYK th'BlIIIBtI-VQIVG'TI 8: issubsequently-repertated" to: its; closed: position I under the: controlof the measuring coil R49 dependent upon the load upon .theioperatingmotor I 6; or; under the control of i the: cam1O3i and'the associatedset. of switch springs S3; all. inithe :manner' previously explained.Inanyrcase, "after" a time'in'terval of approximately 45:secondssfollowingoperationof the drain: valve -22\ intoits='non+draining position,

the intermediate spring of? the set, ofrswitch springs S3 engages thelow portionfoffithewam C3fiopening the contacts 2. andclosingthecontacts I inorder positively to insurede energization. of the inletvalve solenoid i8 and shortcircuiting of the measuring coiLRAfl. At'this time-the inlet valve l8 occupies :its closed' position: and thedrain valve 22 occupies its'nondraining position; whereby the second:rinsing 'st'epvcontinues for a tir'neinterval of approximately90'seconds following operation of the drain: valve, 22 to itsnon-draining position; whereuponthe upper spring of the set of switchsprings :Sd engages the highportion'of the .cam C4. opening the Jassociated contacts" in order to effect de-energization'of the drainvalve solenoid 22' andtheconsequent return'of the drain valve '22 toitstdraining position.

The Washing liquid accumulatedin thesump ISI-isdrained into the drainconduit in the manner previously explained in a short time. interval;and approximately 45 secondsxafter the drain valve 22' is operatedtoits'drainingpositionithe intermediate spring of the set offswitchsprings si engages the highest portion of. the camCZ opening thecontacts I and closing the contacts 2'; When the contacts I of the setof switch springs 32' are thus opened the common point in the circuitfor. energizing the inlet valve solenoid l8 and the drain valve solenoid22"is interrupted, thereby positively toinsure that the inlet valve I8-"occupies its closed position-and the *drain' .valve' 22' occupies itsdraining position in the remainderof the washing cycle. Iii-other Words,the operation of the set of switch springs S2 to 013811113118 contacts Ipositively disables further efie'ctive control of the sets of switchsprings S3 and S4 notwithstanding further operation thereof by therespective cams C3and.C4. In the setiof switch springs 52, closure ofthe'contacts 2 =completes a circuit for energizing the heating element26 that includes the control conductors 13, I6 and 15 and the X contactsof'the set of switch springs S! whereby'heat produced bythe heatingelement '26 in the =vat-l z is circulated' in thesvat -lii by the bladesofthIeimpeller i4 since operation "of the operating 'motor I 6 iscs'ontinued at. this time. The hot air c-irculated'in the vat I2 J by?the: impeller M "is directed into 'contact with andthrou'gh' thedishes'su-pported bythe rack structure; not shown} and thence baek intocontactwiththe heating -element 26.

"This initial drying step is -continued for a time interval ofappro'ximately 12001 seconds where upon-the lowermost-spring" of theset'of switch springs Si: engages the intermediate portion '01? the camClfeifecting opening of the contacts Y while the contacts X are retainedclosed. Opening of I'the contacts Y of the" set ofswit'ch springs S linterrupts the circuit for-operating the operating-motor i6?-whiletheclosed contaets -X of 1E4 the: set:- of iswitch springs SJ": retainscompleted the: circuit for: energizing; the; heating: element 26.-Accordingly;- theco'perating; motor it stops, arre'stingthe rotation'zofthelimpeller MJwhile thewsupply'or-xheat to -the heating element 26continues; Thus drying ofv the dishes supported by the-mack"structure-,rnot shown, continues through: a; final wdrying step'. afteroperation of the-imp'ellerfild" has' been arrested:v The final dryingstep continues for a time' interval of approximately 600 seconds;whereupon the lowermost'spring of the set of switch springs Si engagesthe lowesti'portionfof the? cam CI opening the contactscX';iandlthe'cintermediate spring of the set of switch springsrslengages theintermediate po'rtiornof. the 5 cam AC2 opening the contacts 2:Openingiof the contacts'X' of the set of switch springs: SIinterrupts-the circuit for energizing the "heating elementiZ B: andinterrupts the operating circuitfor theitimer motor'fiii. Also, openingof'thecontacts" 2 T ofi'the set' or switch springs S2 interrupts-aiurther pointin the circuit for energizing the heating elementI26;-Whereby both terminalsfof the heating' elernent' 26* aredisconnected at this time fromr-athe lineconductors 1! andzwor theJsou'rceiof icurrenttsupp'ly.

At'ithisxtime thefs'haft fifl 0f?th'e circuit controller 30 h'as"beenrotated #fromits on position in the clockwisedirection back" into itsofi 'positi'onj 'operatiorr of the circuit controller 33 has beenarrested: I and the washing cycle of the dishwashir'rgv'apparatus' 1 0has been completed. Thus it will she. understood that when themanual-scont'rolkn'ob 55 of thecircuit controller 30 iszrotated from itsoff""position', slightly'greater than-601 degrees in" the clockwisedirection' into its.--on position; further operation of thecircuit'controller 30? is automatically initiated under the *control ofi'th'etimer motor 66. More particularly; the timer motor 65' effects continuedrotation "of: the manual control knob 55in the=clockwiseidirection"fromits onpositi'on hack into its" off "position, 1 whereby operation'ofithe" circuit controller 30"15 automatically arrested;- As theshait flis rotated from its on' positionbackwinto its' ofi position in theclockwise direction, it is rotatedsequentially through the dii ferenti'control positions thereof causingtthe" camsfC'I arrd'tCZrto effect theoperation's'"of the setsiofiswitch springs-S1 and S2; respectivelyrasdescribed'above. Also; the shaft 60i'sfrotat'edin1the=counterclockwisedirection causing the oaths-"C3 and"C4 to'feffect the sequential operatiohs of the sets of "switch springsS3 and S4, respectivelyfas described' above;

Since the shafttD' is"rotated"three revolutions 'thecoiinterclockwisedirection iii bile the shaft otat'ed only one" revolution in theclockwise dire'ctionynoncentrolling :operations by the cams :C3 and C'4-of tlie"setsof switch springs S3 and 84; espectivelyyare'eiiected atthe beginning a iid at tliee'nd of thewashing cycle; however, withouteffect, since the "actual control exerted. by thesets of switch"springsStand Si is negatedb'y the set offs'witch'springs S2 except during onerevomticnsrthe-"Shanta m the intermediate 'portion Y of the" washingcycle. More pa, "cularly; the'sets'ofswitch 'springs's3 and S4 a're'h'dereH'FbperatiVeteefiect' controls only when-the set of sv'vitch"springs 82" is operated. to cl o'se'the-i contacts l'rwhich circumstanceis presen-t inthe-cycl'e only-' duringrotation of the shaft 54 throughthe segmeht of" itsie'volution between 60 and dgrees 'thereof from itsoff posiuchs This rotation of the' sh'aft 54 through 120 degreescorresponds to a complete rotation of the shaft 60 through 360 degrees,as. clearly indicated in Fig. 4. Following this rotation of the shafts60 and 54 and when the shaft 56 reaches its 180 degree position, the cam02 oper ates the set of switch springs S2 in order to open the contactsI, thereby again negating operation of the sets of switch springs S3 andS4.

This arrangement is very advantageous as it permits utilization of thecomplete 360 degrees of periphery of the cams C3 and C4 to effect theoperations of the sets of switch springs S3 and S i, respectively,during the corresponding 120 degrees of rotation of the cams Cl and C2.Thus the arrangement permits the desired fine and accurate controls of'the inlet valve solenoid I8 and the drain valve solenoid 22 repeatedlyin the intermediate 1170 seconds within the washing cycle where thesecontrols are required. Thus the cams CI to C4, inclusive, effectcoordinate operations of the sets of switch springs SI to S4, inclusive,in order to effect the automatic washing cycle of the dishwashingapparatus 10 through the various spraying, washing, rinsing and dryingsteps as explained above.

As previously explained, the friction clutch 62 interposed between theshafts 60 and GI permits rotation of the shaft 60 in either direction bythe manual control knob 55 with respect to the stub shaft 6| at any timeand independently of the timer motor 66 so that any one or more of thesteps in the above-described washing cycle may be selectively omitted orrepeated by appropriate manual rotation of the manual control knob 55 inthe proper direction. For example, the final drying step may be omittedfrom the above-described washing cycle by rotating the manual controlknob 55 in the clockwise direction back into its off position when thecam C2 first operates the set of switch springs S2 to close the contacts2, thereby reducing the length of the washing cycle by approximately 30minutes. This facility is especially useful when it is desired to wash anumber of loads of dishes and automatic drying thereof is not importantto the operator, or hand-drying thereof is particularly wished by theoperator.

During the operation of the dishwashing apparatus H1 in the timedwashing cycle above described, the door [3 must be retained in itsclosed position as previously explained in order to retain the doorswitch S4! in its closed position, as it will be observed that the doorswitch SM occupies an interlock position in the control network, andthat any time the door I3 is operated to its open position, the doorswitch S4! is operated to its open position arresting all operations ofthe dishwashing apparatus I0. Finally at the conclusion of the timedwashing cycle the dishes supported by the rack structure, not shown,have not only been thoroughly washed and rinsed, but they have also beendried. Subsequently, the door l3 may be moved from its closed positioninto its open position and the rack structure, not shown, may be movedout of the vat [2 over the door is in its open position so that thedishes may be removed from the rack structure and placed in a kitchencabinet, or the like, if desired.

In view of the foregoing it is apparent there has been provided indishwashing apparatus an improved cycle control circuit obtaining animproved cycle of operation of the electro-responsive elements thereofthat permits flexibility of operation and achieves accurate andpositivere sponse. While the circuit controller of improved construction andarrangement has been disclosed in the cyclic control circuit of thedishwashing apparatus, it will be understood that it is generally usefulin other program selecting systems, such, for example, as in clotheswashing apparatus, or in other apparatus requiring a prescribed programor cycle of predetermined operations.

While there has been described what is at present considered to be thepreferred embodiment of the invention, it will be understood thatvarious modifications may be made therein and it is intended to cover inthe appended claims all such modifications as fall Within the truespirit and scope of the invention.

What is claimed is:

l. A program selecting system comprising first and second rotatableshafts, speed-change gearing interconnecting said shafts so that wheneither one of said shafts is rotated at one speed the other of saidshafts is driven at another speed, said first shaft having an offposition and an on position and a plurality of control positions andbeing rotatable sequentially from its off position into its on positionand thence through its control positions back into its off position, amanually rotatable member connected to said first shaft for rotating it,an electro-responsive timer operative at a predetermined rate, a driveconnection between said timer and said second shaft for rotating it,said drive connection accommodating rotation of said second shaft bysaid first shaft through said gearing independently of said timer, asource of current supply, switching contacts, an operating circuit forsaid timer including said source and said switching contacts, meansresponsive to rotation of said first shaft by said manually rotatablemember from its off position into its on position for closing saidswitching contacts in order to complete said operating circuit so as toinitiate operation of said timer, said timer rotating said first shaftthrough said drive connection and said second shaft and said gearingfrom its on position through its control positions back into its offposition, means responsive to rotation of said first shaft back into itsoff position for opening said switching contacts in order to interruptsaid operating circuit so as to arrest operation of said timer, saidsecond shaft having a plurality of control positions and being rotatablesequentially therethrough, a first control circuit selectively governedby said first shaft in its various control positions, and a secondcontrol circuit selectively governed jointly by said first shaft in apredetermined one of its control positions and by said second shaft inits various control positions.

2. A program selecting system comprising first and second rotatableshafts, speed-change gearing interconnecting said shafts so that whensaid first shaft is rotated one revolution said second shaft is driven Nrevolutions and so that when said second shaft is rotated one revolutionsaid first shaft is driven l/N revolution, where N is an integer greaterthan 1, said first shaft having an off position and an on position and aplurality of control positions and being rotatable sequentially from itsoff position into its on position and then through its control positionsback into its off position, a manually rotatable member connected tosaid first shaft for rotating it, an electro-responsive timer operativeat a predetermined rate, a drive connection between said timer and saidsecond shaft for rotating it, said drive connection accommodatingrotation of said secndshaft by said first shaft through said gearingindependently of said timer, a source of ourrentisupply, switchingcontacts, an operating circuit forsaid timer including said source andsaid switching contacts, means responsive to rotation of saidfirst shaftbysaid manually rotatable member from its off position into itsonposition for closing saidswitchingcontacts in order to completesaidoperating circuit so as toinitiate operation of said timer, said timerrotating said first shaft through said drive connection and said secondshaft and said gearing from its on position through its controlpositions back into its off position, means responsive to rotation ofsaid first shaft back into its off position for opening said switchingcontacts in order to interrupt said operating circuit so as to arrestoperation of said timer, said second shaft having a plurality of controlpositions and being rotatable sequentially therethrough, a first controlcircuit selectively governed by said first shaft in its various controlpositions, a circuit controller selectively governed by said secondshaft in its various control positions, and a second control circuitselectively governed jointly by said first shaft in a predeterminedsegment of substantially l/N length of rotation thereof and by saidcircuit controller.

3. A program selecting system comprising first and second rotatableshafts, speed-change gearing interconnecting said shafts so that whensaid first shaft is rotated one revolution said second shaft is driven Nrevolutions and so that when said second shaft is rotated one revolutionsaid first shaft is driven l/N revolution, where N is an integer greaterthan 1, said first shaft having an off position and an on position and aplurality of control positions and being rotatable sequentially from itsoff position into its on position and thence through its controlpositions back into its off position, a manually rotatable memberconnected to said first shaft for rotating it, an electro-responsivetimer operative at a predetermined rate, a drive connection between saidtimer and said second shaft for rotating it, said drive connectionaccommodatingrotation ofsaidsecond shaft by said first shaft throughsaid gearing independently of said timer, a, source of current supply,switching contacts, an operating circuit for said timer including saidsource and said switching contacts, means responsive to rotation of saidfirst shaft by said manually rotatable member from its off position intoits on position for closing said switching contacts in order to completesaid operating circuit so as to initiate operation of said timer, saidtimer rotating said first shaft through said drive connection and saidsecond shaft and said gearing from its on position through its controlpositions back into its off position, means responsive to rotation ofsaid first shaft back into its off position for opening said switchingcontacts in order to interrupt said operating circuit so as to arrestoperation of said timer, said second shaft having a plurality of contro1positions and being rotatable sequentially therethrough, a first controlcircuit selectively governed by said first shaft in its various controlpositions, a first pair of switch springs selectively operated betweenopened and closed positions by said first shaft in its various controlpositions, said first pair of switch springs occupying a given positiononly in a predetermined segment of substantially l/N length of rotationof said first shaft, a second pair of switch springs selectivelyoperated between opened and closed positions by said second shaft 18 inits various control positions, and a second control circuitselectivelygoverneds jointly by. said first and second. pairs. of:switch springs.

4i. A program selecting switch comprising a frame, first and secondrotatable shafts.- mounted on said frame, speed-change gearinginterconnecting said shafts so; that when said first shaft is rotated.one revolution said second shaft is driven N revolutions and so. thatwhen said second. shaft is rotated one revolution said first shaft isdriven l/N revolution, where N is an integer greater than 1, a manuallyrotatable member GQDQWIQQ? qrs lid fir t; Shfizfafi f r rotating it,electro-responsive timer operative ata predetermined rate, a driveconnection between said timer and said second shaft for rotating it,said drive connection accommodating rotation of said second shaft bysaid first shaft through said gearing independently of said timer, saidtimer being operative to rotate said first shaft through said driveconnection and said second shaft and said gearing independently of saidmanually rotatable member, first switching mechanism selectivelygoverned by rotation of said first shaft for controlling operation ofsaid timer, normally ineffective second switching mechanism selectivelygoverned by rotation of said second shaft, and third switching mechanismselectively governed by rotation of said first shaft for selectivelyrendering effective said second switching mechanism.

5. A program selecting switch comprising a frame, first and secondrotatable shafts mounted on said frame, speed-change gearinginterconnecting said shafts so that when said first shaft is rotated onerevolution said second shaft is driven N revolutions and so that whensaid second shaft is rotated one revolution said first shaft is drivenl/N revolution, where N is an integer greater than 1, a manuallyrotatable member connected to said first shaft for rotating it, anelectro-responsive timer operative at a predetermined rate, a driveconnection between said timer and said second shaft for rotating it,said drive connection accommodating rotation of said second shaft bysaid first shaft through said gearing independently of said timer, saidtimer being operative to rotate said first shaft through said driveconnection and said second shaft and said gearing independently of saidmanually rotatable member, first switchingmechanism selectivelygovernedby rotation of said first shaft for controlling operation ofsaid timer, normally ineffective second switching mechanism selectivelygoverned by rotation of said second shaft, and third switching mechanismselectively governed by rotation of said first shaft through apredetermined segment of substantially l/N length of rotation thereoffor selectively rendering effective said second switching mechanism.

6. A program selecting switch comprising a frame, first and second andthird rotatable shafts mounted on said frame, speed-change gearinginterconnecting said first and second shafts so that when said firstshaft is rotated one revolution said second shaft is driven more thanone revolution and so that when said second shaft is rotated onerevolution said first shaft is driven less than one revolution, amanually rotatable member connected to said first shaft for rotating it,an electro-responsive timer connected to said third shaft for rotatingit at a predetermined speed, a friction clutch interconnecting saidsecond and third shafts, said third shaft when rotated by said timerdriving said second 19 shaft through said friction clutch, said frictionclutch accommodating slipping of said second shaft with respect to saidthird shaft when said second shaft is rotated by said first shaftthrough said gearing, switching mechanism selectively governed byrotation of said first shaft for controlling operation of said timer,and additional switching mechanism selectively governed jointly byrotation of both of said first and second shafts.

DOUGLAS F. ILLIAN.

References Cited in the file of this patent UNITED STATES PATENTS NumberNumber 20 Name Date Knight Jan. 28, 1941 Schumert Sept. 8, 1942 PearsonMay 3, 1949 Grant May 31, 1949 Clark Apr. 4, 1950 Geldhof et a1. Feb. 6,1951 Horvath July 17, 1951 Dunham July 24, 1951 Oliver Aug. 7, 1951Morrison Dec. 25, 1951

